1. Field of the Invention
The present invention relates to an oil separator, particularly to an oil separator suitable for separating cooling oil from gas discharged from an oil cooling type compressor.
2. Description of the Related Art
In general, in facility using an oil cooling type compressor, an oil separator that blows gas discharged from an oil cooling type compressor into a container so as to inertially separate or centrifugally separate cooling oil contained in the discharged gas is widely used.
Japanese Unexamined Patent Application Publication No. S57(1982)-127883 describes an invention of an oil separator in which a fluid inlet is provided in an upper part of a side wall of a vertical type cylindrical container, a fluid outlet is provided in an upper lid of the cylindrical container, and an oil separation element is provided so as to cover the fluid outlet, wherein an inner cylinder is provided so as to surround the oil separation element, a partition plate seals a space between the cylindrical container and the inner cylinder at a position near the fluid inlet, and a fluid entering the cylindrical container performs circular motion through a flow passage between the cylindrical container and the inner cylinder so as to centrifugally separate cooling oil, enters the interior of the inner cylinder from an inflow port provided in the vicinity of the partition plate, passes through the oil separation element, and flows out of the fluid outlet.
In recent years, in order to improve a maintenance property and to reduce a pressure loss in an oil separator, a small oil separator with a simpler configuration is desired. At the same time, improvement of an oil separation performance is also strongly desired. A heat exchanger (a condenser) of a refrigeration device particularly shows an extremely low heat exchanging performance when a mixed amount of oil exceeds a certain amount. Thus, a sufficient oil separation capability is required for an oil separator provided between an oil cooling type compressor and a heat exchanger (the condenser).